<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>screen</title>
</head>
<body>

<script type="text/javascript">

    console.log( navigator.userAgent ) ;
    console.log( screen.availHeight);
    console.log( screen.availWidth);
    console.log( screen.height);
    console.log( screen.width);

</script>

</body>
</html>